Dumbbell



1. Dumbbell

FIG. 1.1 is a front, top, left side perspective view of a dumbbell showing my new design;

FIG. 1.2 is a front view thereof;

FIG. 1.3 is a front, top, right side perspective view thereof;

FIG. 1.4 is a front, bottom, left side perspective view thereof; and

FIG. 1.5 is a left side view thereof. 

CLAIM The ornamental design for a dumbbell, as shown and described. 